Nailing machine



F. L. BRANDT NAILING M4CHINE June 20, 1939.

Filed Sept. l, 1937 3 Sheets-Sheet 1 June 20,V 1939.

F. L.. BRANDT MAILING MACHINE Filed Sept. 1, 1937 3 Sheets-Sheet 2 l," ww

Wvg/WDR F. L. BRAND-r MAILING MACHINE June 20, 1939.

Filed Sept. l, 1937 3 Sheets-.Sheet 3 Patented June 20, 1939 l PATENT UFFICE NAILING MACHINE Francis L. Brandt, Marblehead, Mass., assigner to United Shoe Machinery Corporation, Paterson, N. J., a corporation of New Jersey Application September 1, 1937, Serial No. 161,980 j 1s claims. (c1. i-faz) My invention relates to machines for inserting such fastenings as nails, it being particularly applicable to the driving of nails from within shoes to secure heels thereto.

In the attachment of the heels, especially those o-f wood of the character employed in womens work, it is desirable to incline the nails inwardly. This is because their entering points in the heelseat should be comparatively close to the crease, so this shall be tight yet the nail-points be kept away from the heel-walls, so they shall not break through. This inclination is commonly effected by inclining the nail-engaging ends of the drivers downwardly and inwardly toward the axis of the v shoe-supporting jack in which they operate. This so disposes each nail against the inner side of the driver-passage, tilted inwardly by contact of its head with the passage-wall, that it enters the Work at an inward angle from the vertical, this angle increasing as the resistance by the nail to penetration of the heel is encountered. Because the nail-head is restrained against inward movement by engagement with the passage-wall, said head vis maintained in its initial lateral relation and is therefore compelled to travel in a rectilinear vertical path. It will be seen that the leading or point-portion of the nail is proceeding in one direction and the following or headportion in another. Because of this, the shank must bend, and as this occurs, a component of the driving force is impressed by the shank outwardly upon the heel-material, the effect being frequently to split the heel. As the shank of the nail is thus bent outwardly, the outer edge of the head leaves the end of the driver, while the opposite edge remains in contact therewith at the passage-wall. This causes the angle of the head to the insole to increase, so to properly sink the inner edge of the head the depth of driving at the outer edge must be exsessive. The

difficulty is added to by the fact that the heelclamping pressure may not be adequate, so the insertion of the nails somewhat lifts the work from the jack. There is consequently produced a space between the jack-top and the insole into which the head-portion of the already deformed shank may bend freely, causing the nail to cripple. As soon as the different ydirections of travel of the point and head-portionsy of the shank become substantial, there is added to the splitting action upon the heel a forcing of the inner edge of the head against the passage-wall, wearing this Y and destroying its circular form. It is an object of my invention to so arrange the driver vor drivers of a nailing machine that the nails are properly inserted and to a great extent relieved of the bending, .crippling and heel-splitting forces just indicated.

In the attainment of the above object, a de pression is formed in the work-support or jack about the opening of a driver-passage adjacent to the work, and the driver which reciprocates in this passage has a head movable laterally in the depression. This movement is permitted in the present embodiment of the invention by the capacity of a portion of the driver to shift laterally in the passage, as by flexing, although the head may substantially i'lt the passage. The result of this is that When the head reaches the depression after the nail has been partially driven, it is at once free to move outwardly from the path which it is constrained to follow by engagement with the passage-wall, so as the insection of the nail continues, the head-portion of kthe shank may straighten into substantial alinement with the point-portion which isv within the heel. This removes from the heel the splitting stress and allows the nail-head to assume an angle at which the diiference in the spacing ofthe inner and outer edges from the insole is minimized. With the removal of the bend in the shank the danger of crippling the nail is avoided. Because the driver-head, during the time when the wear upon the passage-wall would be heaviest, is out of engagement therewith, the distortion of the passage is decreased. I add to the effectiveness of sinking of the nail-head in the insole, without disturbing the initial angle at which the nail is inserted, by employing a driver having a concave or curved nail-engaging-surface, the opposite edges of the concavity extendingoutwardly through different distances longitudinally of the driver. This curvature is downwardly and inwardly with respect to the jack. As herein disclosed, the driver has a flexible stem terminating in a head which projects laterally from one side of the stem, this projection being arranged to shift in the depression in the jack-top when the stem bends. The stem may extend from a comparatively rigid shank-portion, by which the driver is secured to its carrier-plate.

l In the accompanying drawings,

Fig. 1 is a Vertical longitudinal section through a jack of a heel-nailing machinek in which my invention is included;

Fig. 2, anenlarged sectional detail upon the line II-V-II of Fig. 1;

` Fig. 3, atop plan view of the jack;

Fig. 4, a transverse'section through the jacktop showing the completion of a nail-inserting operation, while Figs. 5 to 9 inclusive, illustrate in enlarged vertical sections, successive positions of a driver and nail during an inserting operation.

I have shown in the drawings a jack I0 and a heel-holddown I2 of a heel-attaching machine arranged for inside nailing, together with a shoe S supported upon the jack and a heel H clamped upon the heel-seat of the shoe by the holddown. The machine is adapted for the insertion of the nails in successive groups, this being eifected by alternately actuating plungers I4, I6 reciprocating in the jack. This duplex action is not of importance in the present connection, and hereinafter only one nail-driver D and its relation to the jack-top I8 will be considered in detail. The others may be similarly formed and positioned.

Taking this driver D as one which is carried by a plate 26 mounted upon the top of the plunger I4, it appears as provided with a shank 22, which at 24 is threaded into the plate and is held against rotation by a nut 2B contacting with the upper face of said plate. From the shank rises a reduced stern 28 terminating in an enlarged head 3S. The relative transverse dimensions of the shank and stem are clearly indicated in Fig. 2 of the drawings, and it should be noted that the overhang of the head-enlargement is at the inner side only of the stem, while at its outer side the periphery of the head substantially coincides with that of the stem. The upper portion of the stem and its head reciprocate under the influence of the plunger I4 in a vertical passage 32 in the jack-top i8. At the upper extremity of the passage is a depression 34 of substantial depth, iive thirty-seconds of an inch having been found suitable. This depression may be of spherical contour, having a wall 36 curved downwardly and inwardly from the work-supporting surface of the jack to the passage. The driver-head 3i! preferably substantially fits the passage to reciprocate therein, but when, in the later portion of its travel in the insertion of a nail-head, it enters the depression, it is capable of swinging inwardly toward the axis of the jack. The stem 28 of the driver is sufficiently flexible to permit this, it shifting laterally in the clearance in the passage 32 toward the axis of the jack. Obviously, were it found desirable, the stem might be secured directly in the plate 2G. The underside of the inwardly projecting portion of the head is shown as curved at 38, having a contour generally complemental to the wall 36 of the depression, so it may ride smoothly over the depression-wall.

The action of the driver D in the insertion of a nail N is illustrated in Figs. 5 to 9, inclusive. In Fig. 5, the driver appears ready to start its upward stroke. The upper nail-engaging surface 40 of the driver-head 30 is concave, it being curved upon the arc of a circle downwardly and inwardly, so the outer edge 42 is higher than the inner 44 and both lie above a tangent to the arc. It is a common practice to form the nailengaging surface at the end of a driver upon an angle of seven degrees to a plane at right angles to the axis, this inclination being downwardly and inwardly with respect to the axis of the jack in which the driver operates. It has been found that this angle is sunicient to insure the movement of a nail-head under the influence of gravity against the inner wall of the driver-passage and thus give the desired toeing-in eifect. This, however, locates the inner portion of the inclined surface so far downwardly from the insole of the shoe being operated upon, that this side of the nail-head can be properly sunk in said insole only by an excessive depth of driving at the opposite or outer side. But, by curving and inclining the nail-engaging surface as just indicated, the outer higher portion will at least give the equivalent of the seven degrees inclination to initially position the nail, while the inner lower side will rise above the seven degrees plane and thus insure the eifective sinking of the inner side of the nailhead. A nail when supplied head-down in the passage 32 will be directed by the inclined surface 40, so the inner edge of its head will rest against the inner side of the passage, and the shank will contact with the juncture 46 between the passage and the depression-walls. This holds the nail with its point inclined inwardly.V As the driver rises, the nail-point passes through the heel-seat of the shoe S into the heel H at approximately the initial inclination. At this time, the

head is prevented from following the direction of travel of the point, because of its contact with the inner side of the wall of the passage, and to compensate for this, the head-portion of the shank bends more and more outwardly with respect to the point-portion, as is shown in Figs. 6 and 7. This may have some outward compressing effect upon the material of the heel, as is indicated in the latter figure, but before the strain becomes excessive, the inner edge of the head will have reached the point at the bottom of the depression 34. As it rises farther, the flexibility of the stem 28 and its capacity to move laterally in the passage 32 permits the driver-head to swing inwardly, its surface 38 riding upon the depression-surface 36. Since the head-portion of the nail is now free to follow the direction of the point, the effect of the pressure of the shank against the wall of the hole which it is forming in the heel is to straighten the nail, as appears in Fig. 8. This places the outer surface of the nail-head as nearly as possible parallel to the insole-surface, considering the inclined direction of insertion. The frictional engagement between the driver-surface 4D and the nail-head compels the driver and the head to move together laterally, so full driving contact between the two is maintained. The outer curved surface 40 adjacent to the edge 42 and the inner edge at 44 are both in driving engagement with the nail-head, and the insertion terminates as is shown in Fig. 9, the edge 44 sinking in the insole the inner side of the nail-head,v the opposite side of said head being but moderately depressed by the opposite margin of the surface adjacent to the edge 42. The completion of the operation for opposite nails is shown in Fig. 4. The insertion is accomplished without splitting strains upon the heel; the straightening of the nail during driving removes the danger of crippling and places the head in a position favorable for sinking in the insole; and the wear is entirely removed from that portion of the jack-top-passage which is ordinarily most subject to distortion.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a nailing machine, a member for contact with the work and provided with a passage about the opening of which adjacent to the work is a depression, and a nail-driver reciprocating in the passage and having a head movable laterally in the depression.

2. In a nailing machine, a member for contact with the work and provided with a passage about the opening ofr which adjacent to the work is a depression, and a nail-driver reciprocating in the passage and having a portion movable laterally in the passage and a nail-engaging head terminating said portion and substantially filling the passage, said head entering the depression in the reciprocation of the driver. f

3. In a heel-attaching machine, a jack provided with passages opening through its workengaging surface and about which passages are depressions, and drivers reciprocating in the passages and having heads movable laterally in the depressions.

4. In a heel-attaching machine, a jack provided with passages opening through its top and about which passages are depressions, and drivers provided with stems reciprocating in the passages and between which and the walls of said passages is clearance but having heads with a greater transverse `dimension than the driverstems and which substantially t the passages, said heads lying entirely outside the passages at thev completion of insertion of the nails.

5. In a heel-attaching machine, a jack provided with passages opening through its top and about which passages are depressions curved upwardly and outwardly, and drivers reciprocating in the passages and having heads movable laterally in the depressions and curved at their inner sides similarly to the depressions.

6. In a heel-attaching machine, a jack provided with passages opening through its top, a driver-plate reciprocating in the jack, and drivers operating in the jack-passages and each having as an integral structure a shank secured to the plate, a stem of less diameter than the shank and a head of greater diameter than the stem,' said head projecting beyond the shank only at the side toward the axis of the jack.

'7. In a heel-attaching machine, a jack provided with passages opening through its top, and

drivers kreciprocating in the passages and veach having a nail-engaging surface curved inwardly and downwardly.

8. In a heel-attaching machine, a jack provided with passages'opening through its top, and l drivers reciprocating in the passages and each having a nail-engaging surface curved inwardly and downwardly, said drivers having a capacity to yield laterally in their passages in the direction of the downward curvature.

10. In a nailing machine, a nail-driver having a concave nail-engaging end, the opposite edges of the cavity extending outwardly longitudinally oi the driver through diii'erent distances.

1l. vIn a nailing machine, a nail-driver having a flexible stem, and a nail-engaging head terminating the stem and furnishing a lateral projection at one side only thereof.

12. Ina nailing machine, a nail-driver having a flexible stem, and a nail-engaging head Yterminating the stem and furnishing alateral projection at one side thereof, the nail-engaging surface of the head being concave and opposite edges cf the concavity extendingoutwardly longitudinally of the driver through diierent distances.

13. In a nailing machine, a nail-driver having a shank, and a exible stem extending therefrom and terminating in a nail-engaging head having a greater transverse dimension than the stern, the nail-engaging surface of the head being curved and inclined with respect to the axisof the driver.

FRANCIS L. BRANDT. 

